Genus Cacajao refers to a group of monkey species commonly known as uakaris. These primates are found in the Amazon basin in South America. Uakaris are divided into four different species, including the black-headed uakari, the Ayres' red uakari, the bald uakari, and the red-handed uakari. Although they belong to the same genus, each species features distinct physical characteristics that distinguish them from one another. Some synonyms for the genus Cacajao include the term "uakari," which is derived from the indigenous South American Tupi language. Uakaris are also sometimes referred to as "cuxiu," "cacajo," or "wakari".